feat(frontend): add description column for SHOW PARAMETERS

[BugenZhao]

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What's changed and what's your intention?

Add description column to SHOW PARAMETERS. Use ParameterInfo to represent it to make it more consistent with session variables.

Checklist

• I have written necessary rustdoc comments
• I have added necessary unit tests and integration tests
• All checks passed in ./risedev check (or alias, ./risedev c)

Documentation

• My PR needs documentation updates. (Please use the Release note section below to summarize the impact on users)

Release note

If this PR includes changes that directly affect users or other significant modifications relevant to the community, kindly draft a release note to provide a concise summary of these changes. Please prioritize highlighting the impact these changes will have on users.

[BugenZhao]

Current dependencies on/for this PR:

• main
  • PR feat(frontend): add description column for SHOW PARAMETERS #15113 👈
    • PR feat(frontend): support tab-completion for [ALTER SYSTEM] SET #15123
      • PR fix(frontend): require primary key for system table #15126

This stack of pull requests is managed by Graphite.

[wangrunji0408]

LGTM